What’s the world’s most popular currency? The dollar? The yen? Actually, it may be frequent-flier points. Major airlines are devising more and more ways for you to earn points with them — besides flying on their planes. And there are more and more things to spend miles on — besides air travel. Here is Fast Company’s roundup of new, interesting, and downright charitable ways to earn and spend your miles.

Want to sail the friendly seas? United won’t hold it against you. For every fully paid cruise that you take in an ocean-view cabin on Norwegian Cruise Line, United will grant you between 1,000 and 5,000 miles.

Mileage Plus holders can donate air-travel miles to several charities (including the American Red Cross and Habitat for Humanity) — as long as the donation totals more than 10,000 miles.

For United travelers, expired miles are now a thing of the past. As long as you either earn or redeem miles at least once every three years, you can hang on to all of your miles.